Prototyping of Ubiquitous Music Ecosystems

3. Designing Ubiquitous Music Systems

Defining design strategies for ubiquitous music encompasses two areas of expertise: interaction and signal processing. The Ubiquitous Music Group (g-ubimus) has been investigating the musical applications of methods based on human-computer interaction and ubiquitous computing techniques. Metaphors for interaction provide abstractions that encapsulate solutions applicable to a variety of activities without making unnecessary technical assumptions (Pimenta et al., 2012). Thus, interaction metaphors materialize general ergonomic principles to fulfill the human and the technological demands of the activity (Keller et al., 2010; Pimenta et al., 2012). On a similar vein, recurring technological solutions can be grouped as interactions patterns (Flores et al., 2010). These patterns are particularly useful when developers face the task of finding suitable strategies to deal with specific interface implementation issues. So far, our group’s research has unveiled four musical interaction patterns: natural interaction, event sequencing, process control and mixing (Flores et al., 2012). Each of these patterns tackles a specific interaction problem. Natural interaction deals with forms of musical interaction that are closely related to handling everyday objects. Event sequencing lets the user manipulate temporal information by freeing the musical events from their original time-line. Process control provides high-level abstractions of multiple parametric configurations, letting the user control complex processes by using simple actions. Mixing can be seen as the counterpart of event sequencing for synchronous interaction. Musical data—including control sequences and sound samples—is organized by user actions that occur in-time. Furthermore, technologically based musical environments also demand tailoring support for sound rendering. Signal processing techniques for creative musical activities have to be developed according to the characteristics of the tasks involved in the creative cycle, the computational resources provided by the support infrastructure and the profile of the target users. Ubiquitous musical activities may involve mobility, connectivity and coordination among heterogeneous devices with scarce computational resources. Thus, carefully chosen software design strategies are a prerequisite to tackle signal processing support in ubiquitous contexts (Lazzarini et al., 2012; Lazzarini et al., 2014).